Releases occur twice per year, classically on-or-about April 1 and November 1. However, as CDs are no longer produced, the development schedule can be more flexible, as the date when the release is "tagged" in CVS no longer needs to be months in advance of the intended release date. Now, tagging the release can occur with very little lead time - release engineering typically would take several days.

6.3's release date was bumped to the 2nd of April, notices were sent @announce on that day, but the forewarning seemed to be insufficient for 6.1 users expecting the 15th to be the EOL for their release, so a patch developed in the interim was compiled for 6.1 along with 6.2 and 6.3.

For some reason the 6.3 page states April 15 though it did state April 2 at one point. I suppose we're not supposed to care.

OpenBSD source code is managed by the Concurrent Versions System, CVS. This system permits all of the developers to work simultaneously, and integrate all of their changes. CVS permits "tag" metadata, and the OpenBSD Project uses tags for management of the three "Flavors" of the OS: -release, -stable, and -current. At the point of -release, the source code is tagged with "OPENBSD_x_y_RELEASE" where x and y define the release number. Any -stable patches applied to the -release are tagged with "OPENBSD_x_y". The active development branch, -current, is untagged.

Yes. Twice per year, -current is used to create -release. This is one of the steps that indicates the release has been prepared. Before public distribution, the release needs binaries built for systems and packages for all architectures, and the Project members need to complete all the many website changes, too.

My install went smoothly, as usual, but this time around, I didn't install Fluxbox, (which is normally the first thing I do), as I promised myself that I would try to use cwm last time, but didn't get around to it, so, with no Fluxbox installed, I have started to use cwm as my GUI.